Objectives Discover how geologists monitor faults. Understand how geologists determine earthquake risk.
Monitoring Faults Geologists place instruments that measure stress and deformation in the crust. This is a means that geologists use to try to predict when and where an earthquake will occur. Highest risks areas are determined by locating faults that are active and where past earthquakes have occurred.
Fault Monitoring Devices Four instruments are used to monitor faults. Creep meters Laser-ranging devices Tiltmeters Satellites
Creep Meters Creep meters use a wire stretched across a fault to measure sideways movement of the ground.
Laser-Ranging Devices Laser-ranging devices use a laser beam that bounces off a reflector that detects even the slightest fault movements.
Tiltmeters Tiltmeters measures how much the ground has tipped along a fault.
Satellites Satellites use radio waves to bounce off the ground to measure changes in elevation.